First of all I must tell that this is my first ever 3D CAD file, so my apologies to all of you as your quality standard is extremely high, and for not having reached that level. I am sorry I did not have knowledge nor time enough, but I did really want to participe in this challenge.
This solution is based mainly in two fluid principles: drag and head loss (hydraulic damper). The effect increases as the wind does, in such a way that for low forces the device has no considerable effect, but for heavy weather conditions it gets blocked, moving smoothly again once the cause dissapears.
The result is a simple but sophisticated solution: the door is attached to an axis in which bottom there is a fin submerged in a tank with mineral oil. The dimensions of the fin and oil tank could seem quite big but they are the necessary to withstand the spec requirements: a wind of 100 kn (this is a very high figure; with this wind force no vessel should sail). With the current attached model the crew members will have to provide seven times their force as a maximum for a wind of 50 kn, but from a wind of 66 kn, the door will block itself, as the dynamic effects of the drag of the fin and the head losses from the fluid passing suddenly through the small gap between the fin and the tank bounderies exceed the wind force (its moment). It is necessary to say that this effect has been calculated for only 1 second time (the time in which a door closes suddenly). This maximum force can be adjusted till 3 times when the fin shape is tuned to fit the surrounding boundaries.
The door axis is divided into three parts for installation easyness (see attached screenshots: lower part attached to the fin, intermediate part attached to the glass door, and the upper part, which slides upwards in a gudgeon on the deckhead – with a fixing bolt to prevent it from moving itself).
The deposit has a bolted cover on deck – with rubber gasket - (not visible as eventually the deck is covered by wood), and with the axis seal in top of it, also bolted. The cover has also a plug for filling the tank (only one time in its lifetime cycle) with oil.
To sum up, the main advantages are:
- Simple solution, easy to install, no maintenance, cost effective.
- Aesthethic solution: minimalist result, simplicity is sophistication.
- Green: withstand the marine environment (in this environment the more simple, the better) with no maintenance and no pollution.
- Easyness of construction: can be made in the own shipyard, or by a subcontractor
- Keeps door esay to open and close in no wind conditions
- No door axis alignment problems
- The oil tank is integrated in the vessel structure
- The exterior parts are stainless steel, but the interior parts (inside the oil tank can be carbon steel)
- Can be used in multiple yacht doors, implementing an standard on many different ships